Volume 140, Issue 7, Pages 1909-1918 (June 2011) Endoscopic Mucosal Resection Outcomes and Prediction of Submucosal Cancer From Advanced Colonic Mucosal Neoplasia  Alan Moss, Michael J. Bourke, Stephen J. Williams, Luke F. Hourigan, Gregor Brown, William Tam, Rajvinder Singh, Simon Zanati, Robert Y. Chen, Karen Byth  Gastroenterology  Volume 140, Issue 7, Pages 1909-1918 (June 2011) DOI: 10.1053/j.gastro.2011.02.062 Copyright © 2011 AGA Institute Terms and Conditions

Figure 1 Examples of Paris classification lesion definitions. (A) Paris 0–IIa granular lesion; histology: tubulovillous adenoma with low-grade dysplasia. (B) Paris 0–Is + 0–IIa granular lesion of the low rectum viewed in retroflexion; histology: tubulovillous adenoma with high-grade dysplasia. (C) Paris 0–IIa nongranular lesion; histology: tubular adenoma with high-grade dysplasia. (D) Paris 0–IIa + 0–IIc nongranular lesion; histology: tubulovillous adenoma with submucosal invasive adenocarcinoma. Gastroenterology 2011 140, 1909-1918DOI: (10.1053/j.gastro.2011.02.062) Copyright © 2011 AGA Institute Terms and Conditions

Figure 2 Example of successful EMR of a large granular lesion. (A) An 80-mm sized Paris 0–IIa granular lesion of the ascending colon. (B) This lesion was resected by sequential inject and resect EMR. The submucosa at resected areas appears blue because of methylene blue dye in the submucosal injection solution. The first resection was performed at the proximal and lateral margins, with a small amount (1–2 mm) of normal tissue at the margin included in the resection. (C) Sequential resections in continuity have removed the proximal aspect of the lesion. (D) The distal (anal) aspect of the lesion is now resected, commencing at the lateral margin. Snare placement is shown, again including a small margin of normal tissue. When closed, the tip of the snare is in continuity with the previous resection margin. (E) Approximately one quarter of the lesion remains, with no mucosal islands evident in the resected area. (F) Successful EMR is achieved. The lesion was entirely resected, resulting in a wide and clean mucosal defect; histology: tubulovillous adenoma with predominantly low-grade dysplasia and focal high-grade dysplasia. Gastroenterology 2011 140, 1909-1918DOI: (10.1053/j.gastro.2011.02.062) Copyright © 2011 AGA Institute Terms and Conditions

Figure 3 Example of successful EMR of a large nongranular lesion. (A) A 45-mm Paris 0–Is nongranular lesion of the sigmoid colon. (B) This lesion was resected by sequential inject and resect EMR. The left side of lesion has been elevated with submucosal injection. (C) The left side of the lesion resected in 2 pieces. (D) Successful EMR is achieved, and the lesion is entirely resected. Diverticulum immediately adjacent to the resection margin is visible. Histology: tubular adenoma with focal high-grade dysplasia. Gastroenterology 2011 140, 1909-1918DOI: (10.1053/j.gastro.2011.02.062) Copyright © 2011 AGA Institute Terms and Conditions

Figure 4 A previous attempt at resection causes submucosal fibrosis and increases the risk of EMR failure. (A) Attempted submucosal injection results in the jet sign, where the fluid sprays back into the lumen at high pressure as it is injected. Submucosal fibrosis has obliterated the submucosal space, resulting in the jet sign, and nonlifting of the lesion. (B and C) Submucosal fibrosis is visible endoscopically during EMR. The white tissue bands are fibrotic deposits caused by electrocautery during the previous resection. (D) Fibrosis is visible histologically with H&E staining of the EMR specimen. Gastroenterology 2011 140, 1909-1918DOI: (10.1053/j.gastro.2011.02.062) Copyright © 2011 AGA Institute Terms and Conditions